Last spring frost
Apr 29
Frost Dates for Millcreek, UT
First fall frost
Oct 22
Growing season
174 days
Hardiness zone
7b
In an average year around Millcreek, UT, the last spring frost (32°F) is about Apr 29 and the first fall frost is about Oct 22, giving roughly a 174-day growing season. To be safe most years, wait until Apr 10 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Jun 9 | May 13 | Apr 25 |
| Freeze (32°F) | May 30 | Apr 29 | Apr 10 |
| Hard (28°F) | May 13 | Apr 12 | Mar 21 |
| Severe (24°F) | Apr 19 | Mar 26 | Feb 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 9 | Jun 1 | May 26 | May 18 | May 13 | May 9 | May 4 | Apr 30 | Apr 25 |
| 32°F | May 30 | May 15 | May 8 | May 2 | Apr 29 | Apr 25 | Apr 21 | Apr 17 | Apr 10 |
| 28°F | May 13 | May 1 | Apr 21 | Apr 17 | Apr 12 | Apr 9 | Apr 4 | Mar 31 | Mar 21 |
| 24°F | Apr 19 | Apr 9 | Apr 3 | Mar 30 | Mar 26 | Mar 17 | Mar 11 | Mar 6 | Feb 28 |
| 20°F | Mar 31 | Mar 20 | Mar 11 | Mar 6 | Feb 28 | Feb 25 | Feb 20 | Feb 15 | Feb 7 |
| 16°F | Mar 6 | Feb 27 | Feb 21 | Feb 17 | Feb 13 | Feb 9 | Feb 4 | Jan 31 | Jan 17 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Sep 27 | Oct 11 | Oct 27 |
| Freeze (32°F) | Oct 6 | Oct 22 | Nov 7 |
| Hard (28°F) | Oct 17 | Nov 1 | Nov 18 |
| Severe (24°F) | Oct 24 | Nov 12 | Nov 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 27 | Oct 1 | Oct 5 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 21 | Oct 27 |
| 32°F | Oct 6 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 26 | Oct 29 | Nov 2 | Nov 7 |
| 28°F | Oct 17 | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 4 | Nov 8 | Nov 13 | Nov 18 |
| 24°F | Oct 24 | Oct 30 | Nov 4 | Nov 7 | Nov 12 | Nov 16 | Nov 19 | Nov 24 | Nov 28 |
| 20°F | Nov 2 | Nov 9 | Nov 14 | Nov 18 | Nov 22 | Nov 25 | Nov 29 | Dec 3 | Dec 8 |
| 16°F | Nov 12 | Nov 19 | Nov 25 | Nov 28 | Dec 2 | Dec 7 | Dec 11 | Dec 15 | Dec 22 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Cottonwood Weir, Ut, about 4.1 miles away@if(!empty($station['elevation_ft'])), at 4,986 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Millcreek, UT?
On average, the last spring frost (32°F) around Millcreek, UT is about Apr 29. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 10.
When is the first frost in the fall?
The first fall frost around Millcreek, UT typically arrives about Oct 22. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 29 on average, or Apr 10 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 174 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 84124 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026